1. Field of the Invention
The present invention relates generally to a composite bat. More specifically, the barrel of the composite bat has greater stiffness in the sweet zone due to a layer of axially oriented fibers.
2. Description of Related Art
Composite materials are commonly used for high performance bats in diamond sports, particularly in softball. While composite materials may be expensive, composite materials may offer some advantages over more traditional materials, such as wood and metal, in terms of targeted strength and weight management.
Of the materials typically used to construct bats, composite materials allow for the most design flexibility and customization. Composite materials or composites are materials made from two or more individual materials. Composite materials may be formed of fibers embedded in a matrix. For example, a carbon fiber resin matrix composite material is made of carbon fibers embedded within an epoxy resin matrix. The carbon fibers have a high toughness and are typically brittle. The toughness of a material refers to the ability of that material to resist fracture. The brittleness or ductility of a material refers to the tendency of that material to deform prior to fracture. The more brittle a material, the less that material deforms prior to fracture. The more ductile a material, the more that material deforms prior to fracture. Most matrix materials tend to be ductile but not very tough. In other words, longitudinal stiffness, moment of inertia, mass, and center of gravity may be more precisely controlled using such design factors as type of matrix material, type and modulus of the fibers, orientation of the fibers, and number of layers or thickness of the composite.
Efforts have been made to increase the ability of a bat to rebound a ball efficiently, particularly in a region of the barrel known as the “sweet spot”. In the sweet spot, the rebounding effect tends to be greater than at other points along the length of the barrel. The sweet spot of a bat may include much of the length of the barrel. Although the shape of the barrel is not generally altered, the stiffness of the barrel may be manipulated to increase the rebounding effect. However, increasing the stiffness of the barrel often simply involves increasing the amount of material in the barrel. Increasing the amount of material in the barrel tends to increase the weight of the barrel. A heavier bat typically leads to slower swing speeds and less powerful hits.
Therefore, there exists a need in the art for a bat having increased stiffness in the sweet spot while effectively managing weight.